/*
 * Copyright 2025 LinQingYing. and contributors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * The use of this source code is governed by the Apache License 2.0,
 * which allows users to freely use, modify, and distribute the code,
 * provided they adhere to the terms of the license.
 *
 * The software is provided "as-is", and the authors are not responsible for
 * any damages or issues arising from its use.
 *
 */

package org.cangnova.cangjie.utils

sealed class ArrayMap<T : Any> : Iterable<T> {
    abstract val size: Int

    abstract operator fun set(index: Int, value: T)
    abstract operator fun get(index: Int): T?

    abstract fun copy(): ArrayMap<T>
}

internal object EmptyArrayMap : ArrayMap<Nothing>() {
    override val size: Int
        get() = 0

    override fun set(index: Int, value: Nothing) {
        throw IllegalStateException()
    }

    override fun get(index: Int): Nothing? {
        return null
    }

    override fun copy(): ArrayMap<Nothing> = this

    override fun iterator(): Iterator<Nothing> {
        return object : Iterator<Nothing> {
            override fun hasNext(): Boolean = false

            override fun next(): Nothing = throw NoSuchElementException()
        }
    }
}
